Injection pump valve



aaaaaa wa Nov. 25, 1969 Filed Nov. 2, 1967 N 5, 1969 u. u. KELLER ET AL3,479,999

INJECTION PUMP VALVE Filed Nov. 2, 1967 3 Sheets-Sheet 2 NOV. 25, 1969U. KELLER ET L INJECTION PUMP VALVE 3 Sheets-Sheet 5 Filed Nov. 2, 1967United States Patent 3,479,999 INJECTION PUMP VALVE Ulrikh UlrikhovichKeller, Tambovskaya ulitsa 75, kv. 85; Adolf Nikodimovich Ledokhovich,Tambovskaya ulitsa 75, kv. 59; Jury Alexeevich Bitjugov, Blagodatnayaulitsa 34, kv. 18; and Geunady Yakovlevich Stratulatov, Vasigevskyostrov 2, Linia 61, kv. 22, all of Leningrad, U.S. .R.

Filed Nov. 2, 1967, Ser. No. 680,140 Int. Cl. F02b 15/00, 49/00 US. Cl.123-139 6 Claims ABSTRACT OF THE DISCLOSURE A valve system for thedelivery stage of a fuel injection pump for internal combustion enginesprovided with spring-loaded delivery and check valves, an; openingthrough which fuel passes to the check valve for effecting openingthereof and a throttle opening in the delivery valve in the fuel flowpath from a delivery fuel line to a pump with the check valve beingopen. The cross section of the throttle opening is smaller than that ofthe opening through which fuel passes to the check valve.

The present invention relates to internal combustion engines, and moreparticularly to valve systems for the delivery stage of fuel injectionpumps.

Known in the art are valve systems for the delivery stage of fuelinjection pumps which incorporate a springloaded pressure valve and aspring-loaded check valve arranged in succession along the path of thefuel to be delivered.

The main disadvantages of the hitherto known valve systems of such typeare as follows:

The highly strenuous working conditions of the check valve which takesup the entire back pressure impact of the fuel, whereby dependabilityand stability of operation of the valve systems become impaired; therelief of the fuel line and the stability .of damping wave oscillationstherein depend entirely on the accuracy of making the component parts ordevices responsible for the operation of the check valve (such as thespring opening in the valve seat and the like), so that it is difiicultto ensure the identical operation of several valve systems and, hence,uniform delivery of the fuel to the cylinders.

An object of the present invention is to eliminate the abovedisadvantages and provide a valve system for the delivery stage of afuel injection pump which is relatively simple in design and whichensures a stable and uniform delivery of the fuel.

According to the present invention, the above object is attained sincethe delivery value or the seat thereof, in the path of the fuel from thedelivery fuel line to the pump, with the check valve being open, isprovided with a throttle opening having a cross section smaller thanthat of an opening through which the fuel passes to the check valve forthe latter valve to be opened.

In the preferred embodiment of the present valve system of the deliverystage, it is advisable for the throttle opening to be provided in thedelivery valve, and with the opening passing the fuel to the check valvebeing in the seat thereof. The latter opening should be located ahead ofthe throttle opening along the path of the fuel flow from the deliveryfuel line to the pump.

It is also possible for the throttle opening and the opening passing thefuel to the check valve to be provided sequentially in the deliveryvalve so that such openings are in communication with the check valvebeing urged against the delivery valve which functions as its seat.

3,479,999 Patented Nov. 25, 1969 A test model of the present valvesystem in the delivery stage of a fuel injection pump proved capable ofproviding dependable operation of the pump under cyclic feed conditions(up to 250 cu. mm. per cycle); high pump capacity with the values of thevalve opening being as small as up to 1.5 mm.; completeinterchangeability of component parts of the same type; and stable anduniform (within 3 percent) feed of the fuel to the cylinders.

Additional objects and advantages of the invention will become morereadily apparent to persons skilled in the art from the followingdetailed specification and annexed drawings and in which drawings:

FIG. 1 is a view in longitudinal section of an embodiment of the valvesystem of the delivery stage with openings provided in the deliveryvalve and in the seat of the check valve;

FIG. 2 is a view in longitudinal section of an embodiment of the valvesystem of the delivery stage with openings provided in the deliveryvalve and in the check valve;

FIG. 3 is a view in longitudinal section of an embodiment of the valvesystem of the delivery stage with openings made sequentially; and

FIG. 4 is a view taken along the line IVIV of FIG. 3 the view looking inthe direction of the arrows.

The valve system of the delivery stage, according to the invention,comprises a seat 1 (FIG. 1) for a delivery valve 2 arranged in a bore 3of a head or body 4 of a pump above an opening 5 serving to pass thefuel delivered by the high-pressure stage to a fuel-injection nozzle(the high-pressure stage and the fuel injection nozzle being not shownin the drawing). The bore 1 is pressed to the bottom of the seat 3through a gasket 6 by a high-pressure fuel pipe union 7.

An axial passage 8 formed in the seat 1 is a continuation .of theopening 5 in the head and upper end face 9 of the seat 1 is engaged bythe delivery valve 2 due to the action of a spring 10 biased between ashoulder in the union 7 and the valve 2 at the moment when the fueldelivery to the fuel-injection nozzle is discontinued. Hence, freetransfer of fuel in the opposite direction is prevented.

Bearing against the delivery valve 2 is one end of a cylinder 11 of acheck valve 12, and by virtue of a spring 13 located within thecylinder, the valve 12 closes an opening 14 provided in end 15 of thecylinder. The opening 14 serves to transfer the fuel from the deliveryfuel line (not shown in the drawing) to the pump after the deliveryprocess effected by the delivery section has been discontinued. Thecross-section of the opening 14 determines the moment when the checkvalve 12 starts to open. In the delivery valve 2 in the path of thereverse flow of the fuel (from the fuel-injection nozzle to the pump),there is provided a throttle opening 16 having a cross-section smallerthan that of the opening 41.

The opening 16 serves to reduce the velocity of the reverse flow of thefuel, thus diminishing the pressure impact affecting the check valve 12and stabilizing the relief of the fuel line (complementing the efiectproduced by the check valve 12). At the moment when the feed is started,the fuel passing through opening 5 (FIG. 1) and passage and contacts 8the delivery valve 2 and, having overcome the resistance of the spring10, forces the delivery va-lve 2 slightly in an upward direction. Thenthe fuel fills the space above the valve 2 in the union 7 and passesinto a high-pressure fuel line connected to the fuel-injection nozzle.

At the moment when the fuel supply is arrested, the delivery valve 2,under the action of the spring 10, is rapidly forced onto the seat 1,opening check valve 12, and the fuel entering through the opening 14starts to pass through the throttle opening 16 into the space above theplunger of the pump (not shown in the drawing), until a pre-determinedpressure is developed in the space above the valve. The throttle opening16 damps the stream of fuel, thus contributing to the damping action ofthe check valve 12 with respect to wave oscillations arising in the fuelline and increasing stability and dependability of its operation.

It will be noted that in the embodiments illustrated in FIGS. 2 and 3corresponding components bear the same reference numbers as in FIG. 1.

In certain situations it is expedient that a check valve 12a (FIG. 2)provided with a spring 13a be arranged in a passage 8a provided in theseat 1 of the delivery valve 2 which, in turn, serves as a seat for thecheck valve 12a closing the throttle opening 16.

In some situations it may be advisable for the throttle opening 16 (FIG.3) and the opening 14, which determines the moment at which the checkvalve 12a comt 1 mences to open, be formed sequentiallyin the deliveryvalve 2 and be in communication with each other. The check valve 12a isprovided'with a cylindrical portion 18 which serves as a guide for-.thespring 1311 and the upper guideportion of a non-return valve 17 havinggrooves 19 (FIG. 4) for passing the fuel.

We claim: 1. A valve system for the delivery stage of a fuel injectionpump for internal combustion engines, comprising:

A body having a bore therein; spring-loaded delivery and i check valveslocated in the bore; one of said valves having a recess passing fuel tosaid c-heck'valve to cause opening thereof; said delivery valve having athrottle opening along its longitudinal axis in the path of fuel flowfrom a delivery fuel line to the pump with said check valve in an openposition; said recess and opening being coaxial and the cross section ofsaid throttle opening being smaller than the cross section of the recesspassing fuel to said check valve to effect opening of the check valve.

2. A valve system for the delivery stage of a fuel injection pump forinternal combustion engines; comprising: A body having a bore therein; avalve seat Within said bore; a spring-loadeddelivery valve within saidbore for cooperation with said seat; a spring-loaded check valve withinsaid bore axially spaced from said delivery valve; said check valveincluding a cylinder having a closed end provided with an opening forpassing fuel and an opposite end bearing against said delivery valve,said delivery valve being provided with a throttle opening along itslongitudinal axis in the path of fuel flow from a delivery fuel line tothe pump with said check valve in an open position; said opening beingcoaxial with the throttle opening and the cross-section of said throttleopening being smaller than the cross-section of the opening passing fuelto said check valve to effect opening of the check valve. 3. A valvesystem for a fuel injection pump for internal combustion engines,comprising: a body having a bore therein for providing communicationbetween a fuel pump and a delivery conduit; a valve seat within the borehaving a flat support surface; a delivery valve having a flat supportsurface for coaction with the flat support surface of the valve seat;said delivery valve having a throttle opening along its longitudinalaxis; a check valve in the bore spaced axially from said delivery valve;said check valve including a cylinder having a closed end and a flangedend; said flanged end resting on said delivery valve; said closed endhaving an opening for delivering fuel; said opening being coaxial withthe throttle opening; a seat provided about said opening; a check valvewithin said'cylinder; a'spring biased between the check valve andthedelivery valve for pressing said check valve against its seat; andsecond spring means surrounding the cylinder biased between a shoulderwithin the bore and said flanged end of said cylinder for pressing saiddelivery valve against its seat. I

' 4. The valve system as claimed in claim 1 in which said bore isprovided with means defining a valve seat for said delivery valve; saidvalve seat having a flat support surface; said delivery valve having aflat support surface resting on said valve seat flat support surface;and said check valve being arranged within said valve seat definingmeans. 5.'The valve system asv claimed in claim 4 in which said recessin said check valve is next to said throttle opening.

6. The valve system as claimed in claim 4 in which said recess isprovided at the end of said throttle opening next to the check valve.

References Cited UNITED STATES PATENTS LAURENCE M. GOODRIDGE, PrimaryExaminer

